| Texto completo | |
| Autor(es): |
Oliveira, Igor G. S.
;
Gallina, Fernando C.
;
Affonso, Muriel R.
;
Bimbi, Fausto E.
;
Souto, Robson S.
;
Lanza, Marcos R. V.
;
Martelli, Silvia M.
;
Barros, Willyam R. P.
Número total de Autores: 8
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of Food Composition and Analysis; v. 148, p. 12-pg., 2025-12-01. |
| Resumo | |
This study presents a novel, highly sensitive electrochemical sensor, PAni/Au/PL6C@Chi/SPPE, for detecting theobromine (TB) in complex food matrices. The sensor is based on a screen-printed polyethylene electrode modified with a nanocomposite of Printex L6 carbon (PL6C), gold nanoparticles (Au), polyaniline (PAni), and chitosan (Chi). Using a phosphate buffer solution at pH 8.0 as the optimal medium, the nanocomposite's surface morphology, wettability, and interfacial electrical properties were characterized by scanning electron microscopy (SEM), contact angle measurements, and electrochemical impedance spectroscopy (EIS), with key parameters optimized for maximum performance. Electrochemical analysis demonstrated that the modified sensor significantly enhanced the TB oxidation current compared to a bare electrode, indicating improved electron transfer kinetics. The optimized sensor exhibited excellent analytical performance, including a wide linear range (0.75-37.00 mu mol L-1), a low detection limit (0.076 mu mol L-1), high selectivity against common interferents, and excellent stability and reproducibility. The sensor's practical applicability was validated by quantifying TB in real samples like chocolate, cocoa powder, and tea, with results showing strong agreement with a comparative UV-Vis spectrophotometric method. This work offers a "fit-for-purpose", lab-made, and cost-effective platform suitable for routine food quality control. (AU) | |
| Processo FAPESP: | 22/04053-0 - Síntese de novos nanocatalisadores heterogêneos à base de ferro (FeSe2 e Fe3O4) para aplicação na degradação de drogas psiquiátricas via processo foto-eletro-Fenton |
| Beneficiário: | Fausto Eduardo Bimbi Júnior |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |
| Processo FAPESP: | 18/22210-0 - EMU concedido no processo 2017/10118-0: cromatógrafo líquido (HPLC) |
| Beneficiário: | Marcos Roberto de Vasconcelos Lanza |
| Modalidade de apoio: | Auxílio à Pesquisa - Programa Equipamentos Multiusuários |
| Processo FAPESP: | 19/06650-3 - EMU concedido no processo 2017/10118-0: sistema potenciostato com módulo de impedância eletroquímica |
| Beneficiário: | Marcos Roberto de Vasconcelos Lanza |
| Modalidade de apoio: | Auxílio à Pesquisa - Programa Equipamentos Multiusuários |
| Processo FAPESP: | 22/12895-1 - Processos avançados para a degradação de poluentes emergentes: materiais catalíticos, sensores eletroanalíticos e divulgação científica |
| Beneficiário: | Marcos Roberto de Vasconcelos Lanza |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |